An autopsy confirmed three men whose bodies were found in a Forestville cabin this week all died of gunshot wounds, the Sonoma County Sheriff's Office reported Friday.

The bodies of a Sonoma County native and two out-of-state men were discovered Tuesday at the rural property near the end of Ross Station Road.

Investigators believe Raleigh Butler, 24, formerly of Sebastopol, Richard Lewin, 46, of Huntington, N.Y., and Todd Klarkowski, 42, of Boulder, Colo., met there to buy a large quantity of pot.

A medical examiner conducted an autopsy Thursday and determined all three were killed by gunfire, the Sheriff's Office said in a written statement.

No other information was released — such as the type or number of weapons used — so as not to jeopardize the investigation, the statement said.

As of Friday afternoon, the Sheriff's Office had not announced any arrests and the killer or killers appeared to remain at large.

Sgt. Carlos Basurto of the sheriff's violent crimes investigation unit did not return calls seeking comment Friday.

Their deaths were just the latest in a series of North Coast slayings tied to the illicit marijuana trade.

Over the past decade, 22 people have been killed in a four-county area, including seven in Sonoma County.

Victims have been found dead in clandestine pot gardens, parked cars or killed in home-invasion robberies. Some law enforcement officials said the violence is being stoked by high profits to be made selling Northern California pot in other states.

The Forestville carnage was discovered Tuesday afternoon by Butler's brother and a girlfriend. Authorities said the men were dead at the scene and there were no signs of a struggle.

Based on interviews and evidence, investigators determined the men were at the cabin to buy marijuana.

It wasn't clear how the men knew each other or who arranged the transaction. Detectives believed Lewin and Klarkowski crossed state lines to complete a deal.